second level caching, cache.EhCache Element NULL

puran · **Joined:** Wed Oct 18, 2006 7:29 am **Posts:** 11

Hello All,

I am trying to have the second level cache working using ehcache. What i see in the hibernate log output is that it adds the entry to the cache but next time it is not able to retrieve it.

Code:

engine.TwoPhaseLoad adding entity to second-level cache: [Person#254]

[30593] cache.EhCache key: Person#254
[30593] cache.EhCache Element for Person#254 is null

my ehcache looks like this

Code:

<cache name="Person" maxElementsInMemory="100" eternal="true" timeToIdleSeconds="300" timeToLiveSeconds="600" overflowToDisk="false" />

I am not sure what might be the reason, only difference is that i am doing these in grails app, i hope that's not a problem.

thanks

gonzao_diaz · **Joined:** Mon Nov 26, 2007 2:29 pm **Posts:** 443

Try increasing the number of elements the cache can hold (currently, 100).
Also try setting overflowToDisk=true, just in case.

Lastly, remember that the cache will only work if you are getting your object using session.load() or session.get().

puran · **Joined:** Wed Oct 18, 2006 7:29 am **Posts:** 11

thanks for the reply,

i am not sure of session.get and load only i have to use HQL as i cannot have get and load only. But i think that's not a problem as i can see the caching happening only for some case it's null.

So i assume max elements is the case i did try increasing that though.. not sure if grails is not picking up my ehcache.xml file.

Thanks

gonzao_diaz wrote:

Try increasing the number of elements the cache can hold (currently, 100).
Also try setting overflowToDisk=true, just in case.

Lastly, remember that the cache will only work if you are getting your object using session.load() or session.get().

gonzao_diaz · **Joined:** Mon Nov 26, 2007 2:29 pm **Posts:** 443

Quote:

not sure if grails is not picking up my ehcache.xml file.

If that were the case, you would see a message on your console output saying something like this

Cache configuration for [your class name] not found, using defaults ...

And I insist. Hibernate only uses the second level cache for session.load() kind of operations, not for the result of random queries.

You can cache queries as well, but this is only valid for queries that are run frequently and with the same parameters.[/quote]

puran · **Joined:** Wed Oct 18, 2006 7:29 am **Posts:** 11

sorry i forgot to mention, i have enabled query cache as well :)
looks like its working, only thing i am trying to do is i don't want any select statements after the first query

may be i am trying too much :) thanks for the help